Solid State Power Amp Reviews

Everyone's going crazy for single-ended power amplifiers. What's the big deal? What is it about these relatively low-powered contraptions that could make everybody so nutso? And has Pass Labs' Nelson Pass completely lost his marbles, selling a 30Wpc amplifier for a price that can buy a high-quality 200Wpc amp? Isn't that 200W amp seven times as loud—and seven times as good—as a 30W amp?

Latest and largest in Krell's current range of power amplifiers, the 600Wpc, $12,500 Full Power Balanced 600 joins the 300Wpc FPB 300 ($9000) and the 200Wpc (originally 150Wpc) FPB 200 ($5900). All are single-box stereo chassis and are specified as "Full Power Balanced"—I think to distinguish the essence of these designs from ordinary stereo amplifiers operated in balanced-bridged mode, usually with impaired performance. The FPB 600's speaker output is balanced; ie, neither "positive" or negative" terminals are connected to ground or the amplifier chassis. (Note that no speaker switches or headphone adaptors, which often have joined channel grounds, may be used, as they will short the outputs.) The output terminals are electrically at 0V, but float above the chassis ground.

Man, you've got to watch out for those preconceived notions—they'll kill you every time. For the last several years I've seen Plinius amplifiers at hi-fi shows and—even though I didn't know the first thing about the company or its products—figured that I knew what they were all about. Spotting their brawny façades festooned with feathery heatsinks, I smugly assured myself that they were some kind of antipodean pretender to the muscle-amp throne—Krell or Threshold wannabes.

Canadian manufacturers enjoy a special relationship with the US market. Though technically their products are "imports," a high level of trade harmony, plus a common continental location, mean that Canadian designs tend to be equably priced in contrast to those exported to the States from overseas.

Canadian electronics manufacturer Bryston Limited has been producing consumer and professional amplifiers since 1974 [see Robert Deutsch's interview elsewhere in this issue—Ed.]. Bryston amps are engineered to be physically and electrically rugged, to meet the stringent demands of professionals, many of whom leave their studio amplifiers turned on for years. While chassis had to be light instead of the audiophile massiveness found in some high-end consumer amplifiers, studio engineers and concert pros continued to favor Bryston amps, which easily passed the "steel toe" test. The 4B, for example, became a standard amplifier for recording engineers and touring musicians.

About a decade ago, I read in Stereophile about the SRC, an add-on remote-control unit manufactured by Acoustic Research. I bought one the next day ('swhat happens when you work across the street from a hi-fi shop). Suddenly I was able to make incremental changes in volume and balance from my listening position—and let me tell you that that's the way to do it. What a phenomenal difference in realistic dynamics and soundstaging.

"Why no review of the Ayre V-3?" queried Stephen Slaughter in July's "Letters" column, echoing several urgent posts to my e-mail address. Word of mouth on this remarkable 100Wpc amplifier was reaching fever pitch. Show reports over the last several years had sounded a consistent note—rooms that demoed with V-3s kept getting mentioned in "Best of Show" overviews. Naturally, this also meant that the pendulum had started its backward swing. "It's not really as good as people are saying," one WCES attendee confided in me. "That's why they won't give it to critics."

Like most audiophiles, I salivate over the latest Jurassic, second-mortgage-inducing power amplifier. Whether it's about the music itself, or simply "my amp is bigger than your amp" one-upmanship, we all know that those who risk a hernia in pursuit of the ultimate in sound invariably come out winners.

The auteur theory of the cinema, first described in the 1950s by François Truffaut, states that a great movie represents the artistic vision of one person, usually the director. Moviemaking may involve collaboration, but it cannot be done successfully by a committee. There has to be a single individual in charge, one whose sensitivity and world view is reflected in the movie. In the same sense that the author of a novel is telling a story through the medium of print, the director of a movie is telling a story through the medium of film.

The No.331 is the latest iteration in a series of Mark Levinson 100Wpc, solid-state, stereo power amplifiers. Extensive cosmetic alterations, internal structural changes, and new circuit designs make it quite different from the No.27 and No.27.5 models that preceded it. These design refinements emanate from Madrigal Audio Laboratories' latest flagship amplifier, the $32,000/pair, 300W RMS Mark Levinson No.33 Reference.

Things didn't start off auspiciously. I'd been after Symphonic Line's Klaus Bunge for more than a year to send me the Kraft 400 Reference monoblocks. Finally he called. He said he was going to be in town for a few days, and he had with him a pair of what he described as his "traveling" Kraft 400s, which he proposed to leave with me.

I remember having a conversation with an audiophile some time ago about the thorny subject of choosing an amplifier. He was convinced, on the basis of an article he had read in Stereo Review, that all amplifiers of a given power rating sound pretty much the same. Although he was sufficiently well off to buy just about anything on the market, he didn't want to waste his money. He chose the amplifier for his system by going through the Audio Annual Directory Issue, calculating the price:watt ratio for each amplifier that was listed, and then bought the amplifier with the lowest price/watt figure that had enough power to drive his speakers. He didn't do any comparative listening and didn't consider buying anything that cost more for the same power, because he knew already that it wouldn't sound any different.

In the fall of 1982, I had just become the Editor of the English magazine Hi-Fi News & Record Review. Hi-fi was in a state of flux. The Compact Disc had just made its debut in Japan, but the British and American launches were six months and a year away, respectively. The Linn orthodoxy prevailed about the role of the source in system performance, but there was no agreement about what was and was not important when it came to enhancing the musical experience. "Objectivists" insisted that amplifiers and even loudspeakers had pretty much reached a design plateau where no further improvement was necessary or even desirable, while "subjectivists" were fragmented. All I was aware of was that my system, based on Celestion SL6 loudspeakers, needed more of an undefinable something.

What is it about a component that makes the blasé High Ender sit up and say, "Hey, this is special!"? What elements of its reproduction reach out to you and won't let go? How does the intrepid audio reviewer find a way to describe these hopefully recurring moments of musical discovery which define the high-end experience? How many times, after all, can you say, "Ooooo, ahhhhh, that's the best [insert some part of the frequency range here]," ad nauseam? How much difference is there, anyway? Therein lies the tale...

I think every audio reviewer hopes for a surprise—when a good, but not outstanding, product is refined by the manufacturer into something special. The review then becomes an exciting discovery, reaffirming the pleasure one takes in good audio, and in listening to music being reproduced as it should be. It makes the listening exciting and the writing easier. The Classé Fifteen solid-state stereo amplifier is just such a surprise.